Hi,
As Adrien said on the AcyMailing forum, you will have to modify the code of the (auto)Subscribe during Joomla registration plugin of AcyMailing in order to use the address values from HikaShop like you want.
You can use that code to get the address data of the user:
if(!include_once(rtrim(JPATH_ADMINISTRATOR,DS).DS.'components'.DS.'com_hikashop'.DS.'helpers'.DS.'helper.php')) return true;
$userClass = hikashop_get('class.user');
$userData = $userClass->get($user['id'],'cms');
$addressClass = hikashop_get('class.address');
$addresses=$addressClass->loadUserAddresses($hikashop_user_id);